schofield



(No Model.) 4 Sheets Sheet 1;

H. P. SGHOPIELD. SAW SHARBENING MACHINE.

No. 574,855.- Paten tBd Jan'. 5, 1897.

(No Model.) 4 Sheets-'Sheet2.

' H. P. SCHOFIELD. SAW ,SH'ARPENING MACHINE.

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llllMlllm "III I lllllllla-i Ill! E 2 4 1mm I I l a I t 4 Sheets- -Sheet 3.

(NoModeL) H. P. SGHO'FIBLD. SAW SHARPENING MACHINE.

Patented Jan. 5, 1897.

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7 (No Model.) 4 Slieets-Sheet 4.

HP. SOHOPIELD; SAW SHARPENING MACHINE.

No. 574,855. I Patented Jan; 5, 1897.

UNITED STATES. PATENT OFFICE.

HENRY P. SOI-IOFIELD, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO L. LARSEN FILSTRUP, OF SAME PLACE.

SAW-SHARPENING MACHINE.

SPECIFICATION forming part of Letters Patent No. 574,855, dated January 5, 1897.

Application filed March 6,1896. Serial No. 582,076. (No model.)

To all whom it may concern: transmitting connections and adjusting fea- Be it known thatI, HENRY P. SOHOFIELD, a tures will be first described. citizen of the United States, residing at Ohi- A guide-standard B is mounted on top of cage, in the county of Cook and State of Illithe frame and is rigidly secured in position. 55 nois, have invented certain new and useful An opening 13 in this guide, Figs. 1 and 7, Improvements in Saw-Sharpening Machines; communicates with the spout extension B and I do hereby declare the following to be a through which the waste matter from the confull, clear, and exact description of the inventacting surfaces. of the grinding-wheel and tion, such as will enable others skilled in the saw is carried away. A vertically-moving 60 art to which it appertains to make and use the gate B is loosely retained in place in the rear same. side of the guide-standard by means of com- This invention relates to improvements in panion removable plates CLCL. (Shown in Figs. the class of automatic saw-sharpening ma- 2 and 7.) The lower part of the grindingchines, and has for its object to provide a dewheel gate B is bifurcated, so as to straddle 6 5 vice of this character embodying certain new the spout B as a matter of convenience. The and novel features in the construction, arupper part of this gate terminates in a rangement, and operation, as will be herein bracket extension at, in which is journaleda after set forth in detail. pivot-spindle a The upper end of an arm Figure 1 is a front elevation of a machine a connects with the lower end of spindle a 70 2o embodying my improvements; Fig. 2, an end On the lower end of arm a is formed a cap elevation; Fig. 3, a horizontal section on line part a which forms the upper half of a jour- 3, Fig. 2, looking in the direction indicated nal-box forthe arbor B carryingthe grinding by the arrow. Fig. 4 is a broken-away front or sharpening wheel A The part a forms elevation of a portion of the working parts, the lower half of the arbor journal-box. 75 most of the supporting-frame being omitted. The bracket-arm extension a of the gate Fig. 5 is a plan of a shifting wheel; Fig. 6, supportsthebeltguide-pulleyscfiaijournaled a broken-away sectional detail on line 6, Fig. therein. Thebelt driving the grinding-wheel 2; Fig. 7, a part plan and part section on line is indicated in dotted lines and runs from the 7, Fig. 2; Fig. 8, a broken-away elevation of pulley a", mounted on counter-shaft a down 80 a part of a saw, illustrating the particularover the guide-pulleys and around pulley a shaped tooth produced by this machine; and on the grinding-wheel arbor. This arrange- Fig. 9, a section on line 9, Fig. 8. ment provides for the rotary and swinging A may represent the different parts of the movement of the grinding-wheel. The grindmain frame supporting the working parts. ing-wheel is adapted to swing on its pivot- 8 5 3 5 The bar A and parts adj ustably secured to spindle a just far enough in opposite directhe front side of the machine serve to hold tions to impart the required bevel to the cutthe saw in proper position during the operating side of the saw-teeth. This swinging tion of sharpening, and are adjustable with movement is transmitted and regulated by reference to saws of different diameters, a means of the following mechanism: One end 0 4o saw of the circular type being indicated by of a connecting-rod B is secured to the arbor dotted lines in Fig. 1. This arrangement for journal-bearing, Figs. 1 and 2, of the grindholding the saw and bringing the same into ing-wheel, as at b, the opposite end being pivposition with reference to the grinding-wheel oted to a plate I), as at 12 the plate being in A is not new in this class of machines, so turn adjustably attached to the upper part 5 that a detailed description will be omitted of a lever O, as shown in Fig. *2. The conand only referred to in a general way. necting-rod B is in two parts, which are In this class of machines that portion supjoined by a threaded connecting-nut b proporting the grinding or sharpening-wheel is viding for the lengthening or shortening of usually referred to as the head and comsaid rod in adjusting the same. The upper mo prises several different parts. The novel feaend of lever O is provided with a number of tures of this particular head and its motionholes 11 so that the position of plate I) may shifting wheel.

be raised or lowered in accordance with the amount of bevel to be given to the teeth. A bracket is bolted to the frame and is provided with a number of holes 19 The lever C is attached to this bracket near its longitudinal center by a pivot-pin I), inserted in one of the holes, the diiterent holes providing for the shifting of the pivotal center of the lever in regulating the throw thereof.

A shifting wheel 0* is mounted on a counter-shaft C, journaled in the lower part of the frame, Fig. 2. This wheel is provided in its periphery adjacent to its edges with two grooves 11 11*, Figs. 2, 3, and 5, separated by a dividing-rib 1/. These two grooves extend but a part of the way around the circumference and merge into the central groove b at either end. Close to one end of the rib b is located a switch-plate (Z, pivoted in place, as at d. The wider end of this switch-plate lies next the partition-rib and gradually narrows to the other end, stopping short of the jnnction of the double and single groove pathway. The upper end of a plate 0", Figs. 2, 3, and (5, is hinged, as at Z), to the lower part of lever O. A friction-roller (l is journaled in the lower end of plate C and is adapted to engage with and traverse the grooved passage in the This wheel rotates in the direction indicated by the arrow in Fig. 5, and, as shown in Fig. 3, the friction-roller d is in the single groove and is closely approaching the switch-plate. In this position the grinding-wheel is square to and parallel with the axis of the saw being sharpened. As the shifting wheel rotates,the friction-roller is diverted into the left-hand passage of the donble-grooved part, which has the effect of throwing the lever end of lever C inwardly and the upper end outwardly and swinging the grinding-wheel so as to bring it into position at an angle with reference to the axis of the saw and impart a beveled edge to the cutting side of the teeth, as shown at (1 Figs. 8 and 9. It will be noted that one corner d" of the switch-plate projects into the path of the friction-roller, which, coming in contact therewith as the shifting wheel rotates,throws the switch over to the opposite position from that shown, so that .on the next time around the roller traverses the right-hand groove and the grinding-wheel is made to swing at the opposite angle, impart a corresponding bevel to the cutting side of the next tooth, and so on alternately. During the time the frictionroller is traversing the central groove in the shifting wheel the grinding-wheel is held in a parallel position with reference to the axis of the saw and in this position has contact with the back of the teeth on the up move ment. This forms teeth with a square back a; and adds greatly to their strength.

The teeth are sharpened and beveled on the down movement of the grinding-wheel and the square back given to the teeth on the up movement, that is, when the drum-wheel is in position so that the friction-roller is in either of the two grooves running side by side the grinding-wheel is on its down movement and is at a beveling angle. \Vhen the grindingwheel reaches the bottom of the tooth and just before it starts on the up movement, the shifting wheel will be in position to bring the friction-roller into the single central groove and throw the grinding-wheel into its square position and in contact with the back of the tooth for the up movement.

The plate C is retained in its working position by means of a pin d, which on being removed will permit of the plate being turned upwardly against the lever (J and out of engagement with the shifting wheel, so that the grinding-wheel. may be operated without the lateral swing for bevelin g purposes and the cutting side of the teeth form ed with a square face.

The grinding-wheel gate is provided on the rear side, Fig. 2, with a bearing-sleeve d for the reception of a red I), extending downwardlytherethrough. The upper end of this rod is provided with ahand-wheel d and the lower end screw-threaded to engage with a lug d formed on a horizontal lever 1). One end of this lever is provided with the pivot-bearing d, the opposite end terminating in the handle d ",so that the grindin g-wheel gate may be raised by hand when necessary so to do.

A cam-wheel I) is mounted on countershaft C and located under horizontal lever l). A friction-roller (Z is journaled to lever l) and has contact with cam-wheel D Now as this cam-wheel rotates it has the effect of imparting a vertical movement to the grindingwheel gate through the connections just de scribed. The gate may be positioned by means of the hand-rod D and the down movement limited by a screw inserted through horizontal lever I) and which is adapted to be adjusted so as to bottom on the frame, so that the friction-roller on lever D may lllNG either a continuous or an intermittent contact with cam-wheel D as the character of the work may require.

A second cam-wheel D is mounted on the front end of counter-shaft 0". This cam has a continuous contact with a roller g, journaled in the lower end of a swinging arm D, the upper end of which is pivoted to the frame, as at 9 A spring g presses against the lower end of arm I) and serves to retain the roller journalcd therein loosely in contact with its cam D. This arm is provided with a slot A bearing-sleeve g is adjustably secured to the arm D by a bolt g, inserted through slot g". A hand-rod E is inserted through this sleeve, the threaded end engaging with a sleeve 9 adj ustably secured to feed-lever E by means of a bolt g inserted through a slot in said lever. The lever E is pivoted at its lower end, as at h, to the frame and provides for a reciprocating movement of the upper end, to which is pivoted one end of feed-finger F, the loose end thereof being adapted to engage with the teeth and rotate the saw so as to bring each tooth in position to be operated upon by the grinding-wheel in the regular order of succession. By means of theswinging arm, the feed-lever, the connecting hand-rod, and the attaching parts a positive and accurate adj ustmentis provided, so that the movement of the saw is easily timed with reference to the movement of the grinding-wheel and also easily and quickly adjusted for saws of different diameters.

Motion is transmitted to counter-shaft C by means of a gear-wheel G, mounted thereon and engaging with a pinion I-I, mounted on a second counter-shaft 11, having the band-pulley H belting with pulley H on the drivingshaft.

Having thus described my invention, What I claim as new, and desire to secure by Letters Patent, is-

I. In a saw-sharpening machine, the con1- bination with a guide-standard, having a fixed position, of a grinding-Wheel gate, provided wit-l1 a bracket extension and having a vertical movement in said guide-standard, a pivotspindle, journaled in said bracket extension, the grinding-wheel and its arbor, a connecting-rod, a lever, a plate, connecting the ad jacent ends of said rod and lever, and a revoluble shifting wheel, adapted to impart the required movement to said lever, substantially as described.

2. In a saw-sharpening machine, the combination with a grinding-wheel and its arbor, supported from a pivotal bearing, of a rod, adjustably connecting said arbor-bearing with a lever, a lever, to which the opposite end of the rod is attached, and a shifting Wheel, having a double-grooved path for a part of its circumference and a single path running into the double path at either end, whereby the grinding-Wheel is set at an angle on the down movement and square with the axis of the saw on the up movement, substantially as described.

3. In a saw-sharpening machine, the combination with the grinding-wheel, of a connecting-rod, a vertical lever, a plate, having a pivotal connection with one end of said rod and adjustably attached to the upper end of said lever, a shifting wheel, provided with both a double and single grooved pathway, a plate, hinged to the lower end of said lever, a friction-roller, journaled in the lower end of said plate and adapted to traverse the grooved pathway in the shifting wheel, and a switchplate, pivoted in the shifting wheel and divertin g the friction-roller alternately into one groove and then the other in imparting a swinging movement to the grinding-wheel, substantially as described.

4. In a saw-sharpening machine, the combination with the lever, (J, of a bracket, provided with a number of holes and to which said lever is adj ustably attached, the shifting wheel, having grooves in its periphery as described, and the plate, hinged to the lower end of lever O and provided with a friction-roller adapted to engage with the grooved periphery of said wheel, substantially as described.

In testimony whereof I affix my signature in presence of two Witnesses.

HENRY P. SGHOFIELD.

IVitnesse-s:

L. M. FREEMAN, L. B. COUPLAND. 

